The public spending watchdog has criticised government departments for being too slow to reduce the amount paid in penalties to the European Commission.
A new report from the Public Accounts Committee (PAC) has found that the UK paid at least £650m in penalties over the past decade because of errors in how public bodies have spent EU funding.
It is calling on the Treasury to 'urgently' address the causes and levels of penalties incurred, and ensure departments share best practice and learn from other EU member states.
Meg Hillier, chair of the PAC, said: 'Government inaction on EU penalties is costing taxpayers dear. Money intended to support projects and programmes in the UK is instead being lost.
'The apparent lack of practical concern about this fact until recently will anger many people, whatever their views on Britain's EU membership. As a priority the Treasury and departments must identify the reasons they keep being penalised and take whatever action is necessary to rectify their mistakes.
'Beyond that, on behalf of taxpayers our committee will expect the announcement of a named official to take responsibility for improving performance in this area.'
The report also called on the Treasury to produce a strategy for using EU funds in the UK, setting out standards for performance and value for money.